Hi,
I'm trying to test openldap-2.3alpha and have build some overlays as
modules, but I'm not loading any overlay modules yet, as a I have
configured just a simple bdb database and a monitor database, nothing
else. When trying to load an initial ldif file with slapadd I get the
error 'overlay_init failed'. Is it a must now, to declare overlays?

No, it's not. However, I note that function is supposed to fal only
if any overlay initialization funtion, among the statically built
overlays, fails. If you built them as dinamical, none of them should
fail. I sugest you dig a bit more into that failure. Also, note that
currently two more features that used to be builtin now moved to
overlays, i.e. the syncrepl and the backglue.

I had no chain overlay configured, not even compiled.
Now I have compiled OpenLDAP-2.3.0alpha without any dynamic loadable
modules but everything compiled in, and installed. The ldif file is
loaded without any complains and slapd runs fine now.
I think I will file an ITS.

Clear; the chain overlay chain_init() function calls some internal of
back-ldap (which the chain overlay is based on) so if the chain overlay
is built as static, and back-ldap is built as dynamic, this call will
surely fail. An ITS might be appropriate.